Hitherto, woven fabrics have been used for covering vehicle seats and some warp knitted fabrics have been used for the same purpose. Weft knitted fabric has potential advantages for use in vehicle upholstery in terms of the ability of weft knitting machines to shape the fabric so that the number of seams required in a seat cover can be reduced. However, the inherent stretchability of conventional weft knitted fabric has been a major factor in preventing its use in vehicle upholstery because it gives rise to unsightly distortion and to damage of the fabric in use.
The present invention is based on the discovery that the choice of the right stitch structure together with a sufficient degree of tightness in that structure, that is a sufficiently small loop size, permit weft knitted fabrics to be produced which are sufficiently rigid and resistant to deformation as to make them suitable for upholstery use and some such fabrics can be made which are able to fulfill the stringent requirements for potential use in upholstery covers for automobile seats. The rigidity required for such upholstery fabric has been assessed as an extensibility in the course and wale directions of 12% or less in each case, when measured by the standard test procedure on a Fryma extensiometer.